This invention relates to modified supported chromium oxide olefin polymerization catalysts.
Supported chromium oxide catalysts can be used to prepare molding grade olefin polymers in a hydrocarbon solution to give a product having excellent characteristics from many standpoints. Such polymer generally has inherently high shear response, for instance. Supported chromium oxide catalysts can also be used to prepare molding grade olefin polymers in a slurry system wherein the polymer is produced in the form of small particles of solid material suspended in the diluent. This process, frequently referred to as a particle-form process, has the advantage of being less complex, but does not produce polymers which are exactly comparable to solution polymers in all rheological properties. There are certain applications where it is necessary to have properties such as high shear response associated with polymers made in a particle-form process.